Field of the Invention
The present invention relates to a solid electrolytic capacitor article, a solid electrolytic capacitor, a lead frame, and a method for manufacturing a solid electrolytic capacitor.
Description of Related Art
Solid electrolytic capacitors having a conductive polymer as the electrolyte are widely known as capacitors that are particularly suitable for miniaturization.
It is known that if external moisture penetrates into these types of solid electrolytic capacitors, then the moisture has an adverse effect on the properties of the capacitor. Accordingly, if placed in a high-humidity environment, various properties tend to deteriorate, and achieving a satisfactory level of reliability is difficult.
For example, Patent Document 1 discloses that the capacitance of a solid electrolytic capacitor changes depending on the environment, due to the penetration of external moisture into the capacitor. Patent Document 1 states that the reason for this change in capacitance is potentially due to direct contact between the partially exposed dielectric coating and external moisture, and consequently discloses a method for coating the exposed surface of the dielectric coating with a silicone oil.
In recent years, in order to enhance the performance of solid electrolytic capacitors, investigations have also been conducted into the valve action metal used for the anode body. For example, Patent Document 2 discloses a solid electrolytic capacitor which uses a sintered body of a tungsten powder for the anode body. A solid electrolytic capacitor which uses a sintered body of a tungsten powder for the anode body is able to manufacture a larger capacitance than solid electrolytic capacitors which use sintered bodies of other valve action metals. However, cracking of the coating during the chemical conversion step, and a large leakage current tend to be problematic, and therefore investigations are ongoing.